Coaxial cables are widely used to carry high frequency electrical signals. Coaxial cables enjoy a relatively high bandwidth, low signal losses, are mechanically robust, and are relatively low cost. One particularly advantageous use of a coaxial cable is for connecting electronics at a cellular or wireless base station to an antenna mounted at the top of a nearby antenna tower. For example, the transmitter located in an equipment shelter may be connected to a transmit antenna supported by the antenna tower. Similarly, the receiver is also connected to its associated receiver antenna by a coaxial cable path.
A typical installation includes a relatively large diameter cable extending between the equipment shelter and the top of the antenna tower to thereby reduce signal losses. For example, CommScope, Inc. of Hickory, N.C. and the assignee of the present invention, offers its CellReach® coaxial cable for such applications. The cable includes a smooth wall outer conductor that provides superior performance to other cable types. The smooth outer wall construction also provides additional ease of attaching connector portions to the cable ends in comparison to other coaxial cable types, such as corrugated outer conductors, for example.
A typical coaxial cable connector for such a coaxial cable includes a tubular housing or body to make an electrical connection to the outer conductor of the coaxial cable and a center contact to make electrical connection to the inner conductor of the coaxial cable. The center contact may include a tubular rearward end to receive the inner conductor of the coaxial cable. An insulator assembly supports the center contact concentrically within the housing. The insulator assembly may typically include multiple cooperating parts.
A typical connector may also include a gripping member or ferrule that is positioned onto the end of the outer conductor and adjacent the outer insulating jacket portion of the coaxial cable. The ferrule is axially advanced into the housing as a back nut is tightened onto the rearward end of the housing. One or more O-rings may be provided to environmentally seal the connector to prevent the ingress of water, for example, into the connector.
Representative patents directed to coaxial cable connectors include U.S. Pat. No. 6,396,367 B1 to Rosenberger; U.S. Pat. No. 6,024,609 to Kooiman et al.; U.S. Pat. No. 6,607,398 B2 to Henningsen; and U.S. Pat. No. 6,217,380 B1 to Nelson et al. The entire contents of each of these patents is incorporated herein by reference.
One important consideration in reducing the costs of connectors may be the number of connector components that are manufactured and then assembled to produce the connector. Another consideration in connector design may be accommodating the axial movement of the back nut and end of the cable into the connector housing as the back nut is tightened so that good electrical contact is maintained.
Published U.S. Patent application No. 2005/0118865 to Henningsen discloses a coaxial connector including a back nut that threads onto the rear of a connector body. The connector body carries a dielectric spacer at its front end that, in turn, carries a center contact for electrically connecting to the inner conductor of the coaxial cable. The cable end is prepared by manually passing it through the back nut and then manually flaring the outer conductor. The flared portion of the outer conductor is ultimately gripped between a ramp on the rear end of the connector body and a corresponding ramp on the back nut. Unfortunately, flaring the outer conductor requires an additional manual step that needs to be done properly to ensure good contact with the outer conductor.